What are the safety problems of lithium-ion power lithium-ion batteries

First, in terms of electrochemical significance, compared with other materials, lithium batteries take into account the specific energy, safety, specific power, life and other characteristics required by electric vehicles, as well as relatively low cost. In the past, lithium batteries were mature without new material systems. It should be a good choice for the development of electric vehicles. Judging from the development of global lithium-ion power lithium-ion battery technology, there are theoretical solutions to safety issues. However, to ensure the safety of vehicles equipped with lithium batteries is not only a technical issue, nor is it just the material itself. The issues with battery cells also include the improvement of related Ru0026D and manufacturing management systems, as well as the enhancement of collaboration and cooperation between all parties. Second, we should speed up the establishment of a cross-category power lithium-ion battery safety evaluation system. At the recent academic conference on lithium-ion power lithium-ion battery safety technology held by the Chinese Academy of Engineering, Academician Chen Qingquan of the Academy of Engineering issued an appeal: the power lithium-ion battery safety evaluation system is the key and the most important. During the meeting, Dr. Fang Wang from the Laboratory of my country Automotive Technology Research Center analyzed the progress of the safety detection standards for automotive power lithium-ion batteries led by the Ministry of Industry and Information Technology, including BMS function detection, vibration detection, collision and impact detection, fire detection, water immersion detection, etc. However, some experts at the meeting proposed that in addition to traditional detection standards, it is necessary to accelerate the prediction of battery safety probability, the evaluation of in-use batteries, and to enhance the control of harmful gases such as CO and HF (hydrogen fluoride) that are very harmful to the human body after the battery explosion. Research on relevant standards, and require materials, batteries, and car companies to participate in the formulation and improvement of relevant standards, and establish standards including command Ru0026D and processing consistency, evaluation of new and in-use batteries, and reduction of injuries after accidents, etc. Systematic safety evaluation system. Third, although thermal runaway is the fundamental cause of lithium-ion power lithium-ion battery safety, whether it occurs is closely related to heat generation and rate, ambient temperature, and humidity. In other words, it is a problem of probability. How to reduce the probability? At present, the big challenge is that related materials and batteries, batteries, and vehicle companies have to work closely together. This is of utmost importance. Because different vehicle companies, different models, different use conditions and environments have different technical requirements for batteries and battery systems, if there is no sufficient exchange and cooperation between battery companies and car companies in the vehicle development stage, the potential safety hazards of battery systems are difficult to prevent. For example, the battery cell capacity affects the safety problem. The thermal runaway theory proves the single capacity limit, and the small-capacity battery has high safety (such as 10Ah or less). However, some vehicle companies require from the vehicle or the design, and there is no need for the battery. With sufficient knowledge of safety features and sufficient knowledge of relevant safety technologies, buying a cell phone battery is the same as buying a cell phone battery and using large-capacity batteries to form a group system. The lack of technical protection to effectively guard against thermal runaway has led to frequent safety accidents. Fourth, to expand, the most important manifestation of battery safety issues is combustion and explosion. The fundamental reason for its mechanism is thermal runaway caused by short circuit and overcharge. Therefore, beware of thermal runaway caused by short circuit and overcharge is to deal with lithium-ion power lithium The main attack direction of ion batteries. The causes of short circuit are material factors, process factors, and factors such as low-temperature charging, high-current charging and discharging, and rapid negative electrode decay during use. The overcharge is mainly caused by high current charging. At present, the critical path to guard against thermal runaway is: in terms of materials and technology, the development of flame-retardant diaphragms, electrolyte systems, and negative electrode insulation layers, etc. The critical issue is how to achieve high-temperature flame-retardant, high-strength, environmental protection, easy industrialization and low cost; In terms of core manufacturing, efforts are made to deal with consistency issues, such as dust prevention, dislocation of positive and negative electrodes, pole piece burrs, electrolyte/quality uniformity, etc., which involve both technical issues and quality control capabilities of the processing system; battery design, development Battery self-excitation safety technology enables the battery to have self-protection functions, such as battery spontaneous charging voltage clamping technology and spontaneous thermal control technology; in terms of battery system, develop effective thermal management systems, battery management systems, and high-safety structures. Some of these technologies are relatively mature internationally, and are used in some battery processing or vehicle installations. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous post: Lifespan of ternary lithium battery Advantages and disadvantages of ternary lithium battery